I have a question regarding sideloaded epubs stored on the sd card (this applies to Nook Simple Touch + Nook Glowlight) - would the highlights and notes made be stored on the device or the sd card?

I ask for two reasons:

(1) Would this make exporting highlights and notes easier than if it was stored on the device?

(2) My Simple Touch, for no reason, de-registered and wiped all my sideloaded epubs off the device. I had to re-register the device again and obviously was able to only download Nook content back on the device. Unfortunately, all the notes and highlights for sideloaded epubs were wiped off. If the notes and highlights for epubs remain on the sd card, then it gives me peace of mind that if this problem arises again, I have all my notes and highlights backed-up on the sd card.